Insulator pipes and high voltage insulators with integrated conductors, in particular optical fibers, are known in many variants. European Patent No. 0 265 737 describes such an arrangement where the optical fiber is guided in the form of a spiral along an optical fiber support. The optical fiber support in turn is designed as an insulating filament located in the cavity of the high voltage insulator.
Another arrangement is described in U.S. Pat. No. 3,485,940, where an optical fiber is surrounded by a polyester pipe, which is guided through the shank of the insulator in the longitudinal direction.
European Patent No. 0 146 845 describes another high voltage insulator where the optical fiber is also guided in a groove in an intermediate layer located between the shank and the shields in the longitudinal direction.
In the above-described high voltage insulators, the optical fiber is usually drawn into the prefabricated insulator or insulator pipe. German Patent No. 27 55 734 describes the use of longitudinal grooves for this purpose, which form ducts and accommodate conductors or optical fibers; these ducts are subsequently closed. Similarly, French Patent No. 2 725 302 describes a spiral groove provided in the wall of the insulator and an extruded continuous elastomeric tape placed in this groove. Then the conductor is placed on the top side of this tape and the optical fiber and the tape are pressed together by rolling, for example, so the tape is laid on the bottom of the groove and is pressed into the elastomeric material.
German Patent No. 29 01 872 describes an optical fiber in a longitudinal intermediate layer; the optical fiber is led out of the intermediate layer through bores.
A conventional method of manufacturing high voltage insulators is by winding insulator pipes made of epoxy resins with a fiberglass or synthetic fiber laminate structure. Such insulator pipes are described in the company brochure "MR-Isolierrohre ROTAFIL.RTM. fur die Hochspannungstechnik (ROTAFIL.RTM. MR Insulator Pipes for High Voltage Technology)," form VK23-0/88de.
With such insulator pipes made of wound fiberglass plastic, it is not convenient to provide grooves on the outer periphery as described in French Patent No. 2 725 302, and then reclose them using elastomeric material. This would negatively affect the electric strength, in addition to not providing a homogeneous, mechanically strong outer insulating body surface.